SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Jóhannesson Gauti 1979 ) "

Sökning: WFRF:(Jóhannesson Gauti 1979 )

  • Resultat 1-37 av 37
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Aspberg, Johan, et al. (författare)
  • Intraocular Pressure Lowering Effect of Latanoprost as First-line Treatment for Glaucoma
  • 2018
  • Ingår i: Journal of glaucoma. - : Lippincott Williams & Wilkins. - 1057-0829 .- 1536-481X. ; 27:11, s. 976-980
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: The purpose of this study was to assess the intraocular pressure (IOP) - reducing effect of latanoprost in treatment-naïve patients with newly detected open-angle glaucoma with no restriction of the level of untreated IOP.METHODS: Eighty-six patients (105 eyes) with a diagnosis of open-angle glaucoma received IOP-lowering therapy with latanoprost. The IOP reduction 1 and 3 months after initiation of treatment was recorded.RESULTS: Mean untreated IOP for all eyes was 26.2 mm Hg (ranging from 10 to 51 mm Hg). The mean pressure reduction was 7.9 mm Hg (28%), with equivalent average levels at 1 and 3 months. The reduction in IOP ranged from -2.3 to 25.3 mm Hg after 1 month, and from -1.3 to 33.3 mm Hg after 3 months. The pressure-lowering effect was considerably more pronounced in eyes with higher untreated IOP; the reduction increased by 0.55 mm Hg per mm Hg higher untreated IOP. Four eyes, with untreated IOP within statistically normal limits, had no or negative IOP-reduction. A regression model predicted that IOP reduction ended at untreated IOP≤16 mm Hg. Multiple regression analysis showed that an additional IOP-lowering effect of 1.28 mm Hg was achieved in eyes with pseudoexfoliation glaucoma.CONCLUSIONS: To the best of our knowledge, this paper is the first to report the IOP-reducing effect of latanoprost treatment at all untreated IOP levels in newly detected glaucoma patients. The effect was proportional to the untreated IOP at all levels above 16 mm Hg and better at higher untreated IOP levels, also in relative terms. Our results further confirm the indication of latanoprost as a first-line therapy for glaucoma.
  •  
2.
  • Azuara-Blanco, Augusto, et al. (författare)
  • European Glaucoma Society research priorities for glaucoma care
  • 2023
  • Ingår i: British Journal of Ophthalmology. - : BMJ Publishing Group Ltd. - 0007-1161 .- 1468-2079.
  • Tidskriftsartikel (refereegranskat)abstract
    • Background/Aims: The goal of health research is to improve patients care and outcomes. Thus, it is essential that research addresses questions that are important to patients and clinicians. The aim of this study was to develop a list of priorities for glaucoma research involving stakeholders from different countries in Europe.Methods: We used a three-phase method, including a two-round electronic Delphi survey and a workshop. The clinician and patient electronic surveys were conducted in parallel and independently. For phase I, the survey was distributed to patients from 27 European countries in 6 different languages, and to European Glaucoma Society members, ophthalmologists with expertise in glaucoma care, asking to name up to five research priorities. During phase II, participants were asked to rank the questions identified in phase I using a Likert scale. Phase III was a 1 day workshop with patients and clinicians. The purpose was to make decisions about the 10 most important research priorities using the top 20 priorities identified by patients and clinicians.Results: In phase I, 308 patients and 150 clinicians were involved. In phase II, the highest-ranking priority for both patients and clinicians was € treatments to restore vision'. In phase III, eight patients and four clinicians were involved. The top three priorities were € treatments to stop sight loss', € treatments to restore vision' and € improved detection of worsening glaucoma'.Conclusion: We have developed a list of priorities for glaucoma research involving clinicians and patients from different European countries that will help guide research efforts and investment.
  •  
3.
  • Barkander, Anna, et al. (författare)
  • Influence of laser trabeculoplasty on combined phacoemulsification/Kahook Dual Blade goniotomy
  • 2024
  • Ingår i: Clinical Ophthalmology. - : Dove Medical Press. - 1177-5467 .- 1177-5483. ; 18, s. 1811-1817
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To investigate the influence of laser trabeculoplasty (LTP) on subsequent surgery with combined phacoemulsification/ Kahook Dual Blade goniotomy (phaco-KDB) in patients with open-angle glaucoma or intraocular hypertension.Patients and Methods: Patients undergoing phaco-KDB between 2019 and 2021 were divided into previously LTP treated and previously non-LTP treated, and LTP-treatment included argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT). The primary goal was to investigate if previous LTP influenced later surgical outcome of phaco-KDB. The secondary goal was to investigate if the outcome of LTP could be predictive of the outcome of subsequent phaco-KDB. We also compared IOP-and medication reductions between LTP and non-LTP treated patients.Results: A total of 111 LTP treated patients were compared to 139 non-LTP treated patients. In LTP treated patients, surgical success of phaco-KDB was 82.9%, compared to 88.5% in non-LTP treated patients (P=0.20). Reductions in IOP and medications were similar between groups. Furthermore, within the LTP group, patients with successful LTP-treatment had a subsequent surgical success of phaco-KDB in 80.7%, compared to 83.0% in patients with unsuccessful LTP-treatment (P=0.765).Conclusion: Previous LTP treatment does not predict the outcome of phaco-KDB. Furthermore, no correlation was found between the LTP effect and a later surgical success of phaco-KDB.
  •  
4.
  • Barkander, Anna, et al. (författare)
  • Kahook dual-blade goniotomy with and without phacoemulsification in medically uncontrolled glaucoma
  • 2023
  • Ingår i: Clinical Ophthalmology. - : Dove press. - 1177-5467 .- 1177-5483. ; 17, s. 1385-1394
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To evaluate the 2-year efficacy and safety of Kahook dual-blade (KDB) goniotomy in patients with medically uncontrolled glaucoma.Methods: This was a retrospective case-series study of 90 consecutive patients with primary open-angle glaucoma (POAG) or pseudoexfoliation glaucoma (PEXG) that underwent KDB goniotomy alone (KDB-alone group) or KDB goniotomy in combination with phacoemulsification (KDB-phaco group) during 2019–2020. All patients were uncontrolled on three or more medications. Surgical success was defined as an IOP reduction ≥20% and/or a reduction of one or more medications at 24 months. We also report IOP levels and number of medications from baseline to 24 months, as well as the need for further glaucoma interventions.Results: At 24 months, mean IOP had reduced from 24.8±8.3 to 15.0±5.3 mmHg in the KDB-alone group (P<0.001) and from 22.3 ±5.8 to 13.9±3.0 mmHg in the KDB-phaco group (P<0.001). Medications had reduced from 3.5±0.6 to 3.1±0.9 in the KDB-alone group (P=0.047) and from 3.3±0.5 to 2.3±1.1 in the KDB-phaco group (P<0.001). An IOP reduction ≥20% and/or a reduction with one or more medications was achieved by 47% of eyes in the KDB-alone group and by 76% of eyes in the KDB-phaco group. Eyes with PEXG and POAG responded equally well to the success criteria. During the 24-month follow-up, additional glaucoma surgery or transscleral photocoagulation was performed in 28% of eyes in the KDB-alone group and in 12% of eyes in the KDB-phaco group.Conclusion: In patients with medically uncontrolled glaucoma, KDB had a significant IOP-lowering effect after 24 months, but success rates were higher when KDB was performed in combination with cataract surgery compared to stand-alone treatment.
  •  
5.
  • Barkander, Anna, et al. (författare)
  • Outcomes of iStent inject versus kahook dual blade surgery in glaucoma patients undergoing cataract surgery
  • 2023
  • Ingår i: Journal of glaucoma. - : Wolters Kluwer. - 1057-0829 .- 1536-481X. ; 32:10, s. e121-e128
  • Tidskriftsartikel (refereegranskat)abstract
    • Précis: iStent Inject implantation (iStent) or Kahook Dual Blade goniotomy (KDB) in combination with phacoemulsification have a similar IOP-lowering effect in all stages of glaucoma, and medications are significantly reduced, especially after KDB.PURPOSE: To compare the 2-year efficacy and safety of iStent or KDB in combination with phacoemulsification in eyes with mild to advanced open angle glaucoma.METHODS: A retrospective chart review of 153 patients that received iStent or KDB in combination with phacoemulsification at a single center between March 2019 and August 2020. The main outcome parameters at 2 years were: (1) intraocular pressure (IOP)-reduction ≥20%, with a postoperative IOP ≤18 mm Hg, and (2) a reduction of ≥1 medication. Results were stratified by glaucoma grade.RESULTS: After 2 years, mean IOP was reduced from 20.3±6.1 to 14.2±4.1 mm Hg in the phaco-iStent group ( P <0.001) and from 20.1±6.1 to 14.7±3.6 mm Hg in the phaco-KDB group ( P <0.001). The mean number of medications was reduced from 3.0±0.9 to 2.6±1.1 in the Phaco-iStent group ( P =0.001) and from 2.3±1.0 to 1.5±1.3 in the Phaco-KDB group ( P <0.001). Success regarding IOP-reduction ≥20% with a postoperative IOP ≤18 mm Hg was met by 46% in the phaco-iStent group and by 51% in the phaco-KDB group. A reduction of ≥1 medication was met by 32% in the phaco-iStent group and by 53% in the phaco-KDB group ( P =0.013). Eyes with mild to moderate and advanced glaucoma responded equally well to the success criteria.CONCLUSIONS: iStent and KDB, in combination with phacoemulsification, both lowered IOP effectively in all stages of glaucoma. More medications were reduced after KDB, suggesting that it may be a more effective procedure compared with iStent.
  •  
6.
  • Bengtsson, Boel, et al. (författare)
  • The glaucoma intensive treatment study : interim results from an ongoing longitudinal randomized clinical trial
  • 2022
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 100:2, s. e455-e462
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: The aim of the study was to determine the perimetric rate of glaucoma progression in the ongoing Glaucoma Intensive Treatment Study (GITS) after 3 years of follow-up.Design: This is a randomized, two-centre, prospective open-labelled treatment trial for open-angle glaucoma (OAG). Participants The participants of this study were treatment-naive patients with newly diagnosed OAG, aged 46-78 years, with early to moderate glaucomatous visual field loss scheduled to be followed for 5 years within the study.Methods: Patients were randomized to initial treatment with either topical monotherapy or with an intensive approach using drugs from three different classes, plus 360 degrees laser trabeculoplasty. Changes in treatment were allowed. Standard automated perimetry and tonometry were performed and side-effects documented. All results are presented using intention-to-treat analysis.Results: A total of 242 patients were randomized. After 3 years of follow-up, eight patients were lost to follow-up, six of whom were deceased. The median untreated baseline intraocular pressure (IOP) was 24 mmHg in both arms. The median IOP was almost constant over the 3 years of follow-up: approximate to 17 mmHg in the mono-arm and approximate to 14 mmHg in the multi-treatment arm. Treatment was intensified in 42% of the mono-treated patients and in 7% of the multi-treated patients. Treatment was reduced in 13% of the multi-treated patients. The median perimetric rate of progression was -0.5%/year in the mono-treated group and -0.1%/year in the multi-treated group (p = 0.03).Conclusion: The rate of disease progression was significantly slower in the multi-treated patients than in the mono-treated patients. Further follow-up will show whether this difference is sustained over time.
  •  
7.
  • Bengtsson, Boel, et al. (författare)
  • The Glaucoma Intensive Treatment Study (GITS), a randomized clinical trial : design, methodology and baseline data
  • 2018
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 96:6, s. 557-566
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: The primary objective of the ongoing Glaucoma Intensive Treatment Study (GITS) is to evaluate the effectiveness of immediate intensive treatment in comparison with the commonly recommended stepped regimen on the predicted visual field. The two treatment arms are also being compared regarding quality of life (QoL), intraocular pressure (IOP) reduction, frequency of reported side‐effects, adverse events and adherence to prescribed treatment.Design: A randomized, two‐centre, prospective open‐labelled treatment trial for open‐angle glaucoma.Participants: Individuals aged 40–78 years with previously untreated and newly diagnosed glaucoma with early to moderate visual field loss were eligible.Methods: Patients were randomized to initial treatment either using drug monotherapy in accordance with common glaucoma guidelines or using a more intensive approach including eyedrops containing drugs from three different classes combined with 360° laser trabeculoplasty. The patients are to be followed for 5 years at visits including standard automated perimetry, optical coherence tomography (OPT) and tonometry. Change of treatment is allowed and decided upon jointly with the patient as in conventional glaucoma management.Main outcome: The estimated predicted preserved visual field and QoL at end of expected lifetime.Results: A total of 242 patients, 45% females, mean age 68 years, were randomized. The median untreated IOP was 24 mm Hg, and the median visual field index (VFI), indicating the percentage of a full field, was 92%.Conclusion: Glaucoma Intensive Treatment Study is a clinical trial in which two groups of patients randomized to different initial intensities of IOP‐reducing treatment are being compared with regard to rate of visual field progression and prediction of serious glaucomatous visual field loss at estimated at end of life.
  •  
8.
  • Gustavsson, Simon T., et al. (författare)
  • Nicotinamide prevents retinal vascular dropout in a rat model of ocular hypertension and supports ocular blood supply in glaucoma patients
  • 2023
  • Ingår i: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 64
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE. To investigate whether nicotinamide (NAM) modulates retinal vasculature in glaucoma.METHODS. This was a prospective controlled clinical trial investigating animal and human histopathology. Participants included normotensive and ocular hypertensive rats, postmortem human ocular tissue, glaucoma patients (n = 90), and healthy controls (n = 30). The study utilized histopathology, computer-assisted retinal vasculature analysis, optical coherence tomography angiography (OCTA), and NAM treatment. The main outcome measures included retinal vascular parameters in rats as assessed by AngioTool; retinal vasculature integrity in rats and humans as assessed by histopathology, antibody-staining, and ImageJ-based measurements; and retinal perfusion density (PD) and flux index in humans as assessed by OCTA.RESULTS. A number of vessel parameters were altered in ocular hypertension/glaucoma compared to healthy controls. NAM treatment improved the retinal vasculature in ocular hypertensive rats, with an increase in mean vessel area, percentage area covered by vessels, total vessel length, total junctions, and junction density as assessed by AngioTool (all P < 0.05); vessel wall integrity as assessed by VE-cadherin antibody staining was also improved (P < 0.01). In humans, as assessed by OCTA, increases in PD in the optic nerve head and macula complete image (0.7%, P = 0.04 and 1.0%, P = 0.002, respectively) in healthy controls, and an increase in the temporal quadrant of the macula (0.7%, P = 0.02) in glaucoma patients was seen after NAM treatment.CONCLUSIONS. NAM can prevent retinal vascular damage in an animal model of glaucoma. After NAM treatment, glaucoma patients and healthy controls demonstrated a small increase in retinal vessel parameters as assessed by OCTA.
  •  
9.
  •  
10.
  • Holmlund, Petter, 1988-, et al. (författare)
  • Posture-dependent collapse of the optic nerve subarachnoid space : A combined MRI and modeling study
  • 2021
  • Ingår i: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology. - 0146-0404 .- 1552-5783. ; 62:4
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: We hypothesize that a collapse of the optic nerve subarachnoid space (ONSAS) in the upright posture may protect the eyes from large translamina cribrosa pressure differences (TLCPD) believed to play a role in various optic nerve diseases (e.g., glaucoma). In this study, we combined magnetic resonance imaging (MRI) and mathematical modeling to investigate this potential ONSAS collapse and its effects on the TLCPD.METHODS: First, we performed MRI on six healthy volunteers in 6° head-down tilt (HDT) and 13° head-up tilt (HUT) to assess changes in ONSAS volume (measured from the eye to the optic canal) with changes in posture. The volume change reflects optic nerve sheath (ONS) distensibility. Second, we used the MRI data and mathematical modeling to simulate ONSAS pressure and the potential ONSAS collapse in a 90° upright posture.RESULTS: The MRI showed a 33% decrease in ONSAS volume from the HDT to HUT (P < 0.001). In the upright posture, the simulations predicted an ONSAS collapse 25 mm behind lamina cribrosa, disrupting the pressure communication between the ONSAS and the intracranial subarachnoid space. The collapse reduced the simulated postural increase in TLCPD by roughly 1 mm Hg, although this reduction was highly sensitive to ONS distensibility, varying between 0 and 4.8 mm Hg when varying the distensibility by ± 1 SD.CONCLUSIONS: The ONSAS volume along the optic nerve is posture dependent. The simulations supported the hypothesized ONSAS collapse in the upright posture and showed that even small changes in ONS stiffness/distensibility may affect the TLCPD.
  •  
11.
  •  
12.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Can postoperative dexamethasone nanoparticle eye drops replace mitomycin C in trabeculectomy?
  • 2020
  • Ingår i: Acta Ophthalmologica. - : Wiley-Blackwell. - 1755-375X .- 1755-3768. ; 98:6, s. 607-612
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Compare (a) nonmitomycin C (MMC) trabeculectomy and 1.5% dexamethasone nanoparticle (DexNP) eye drops postoperatively with (b) trabeculectomy with MMC and Maxidex® eye drops postoperatively.Methods: Randomized prospective single masked clinical trial with 20 patients with primary open‐angle glaucoma undergoing primary trabeculectomy. The study group consisted of 10 patients without MMC intraoperatively and postoperative DexNP eye drops, and the control group consisted of 10 patients treated with MMC intraoperatively and postoperative Maxidex®. The drops were tapered out over 8 weeks. The main outcome measures were as follows: rates of complete success, that is intraocular pressure (IOP) within target pressures at different time‐points without IOP‐lowering medication, or reoperation. Secondary outcome measures included the following: relative success rate (with IOP‐lowering medications), number of glaucoma medications and reoperations. Patients were followed for 36 months.Results: Both groups showed similar postoperative course and IOP reduction. Intraocular pressures (IOPs) in the DexNP group and in the control group were 25.6 and 24.4 mmHg, respectively, at baseline. Intraocular pressures (IOPs) were reduced to 13.2 and 14.5 mmHg at 12 months, 11.7 and 12.6 mmHg at 24 months and 11.7 and 12.1 mmHg at 36 months, respectively. There were no statistically significant differences between the groups in absolute (p = 0.36) or relative (p = 1.0) success rates, number of medications (p = 0.71) or reoperations (p = 1.0) between the groups at any time‐point.Conclusions: DexNP eye drops are effective postoperative treatment following trabeculectomy. The potent anti‐inflammatory and antifibrotic effect of DexNP may offer an alternative to mitomycin C in glaucoma surgery.
  •  
13.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Can the prevalence of open-angle glaucoma be estimated from a retrospective clinical material? A study on the west coast of Iceland.
  • 2005
  • Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 83:5, s. 549-553
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: To explore the possibility of estimating the prevalence of open-angle glaucoma (OAG) on the west coast of Iceland using a clinical retrospective material, and to compare that estimate with the results from a recent prospective Icelandic study. METHODS: The compulsory ophthalmological examination for the prescription of eye glasses in combination with information obtained from Statistics Iceland were used to establish the prevalence of glaucoma in Akranes and to estimate the minimum prevalence for the greater west coast area. A recent prospective study from Iceland was used as reference. RESULTS: In all, 79% of 1443 Akranes inhabitants aged 50 years or more had visited the eye clinic at least once between 1996 and 2001. The prevalence of OAG was 4.8% (95% CI 3.6-6.1). The minimum prevalence for the west coast was 3.8% (95% CI 3.2-4.4). The prevalence increased with age (p < 0.001). The overall prevalence was similar to that of recently published prospective data but the prevalence of normal tension glaucoma (NTG) was lower. CONCLUSION: The results from the two studies are similar in many respects, which indicates that retrospective data may supply meaningful information on glaucoma prevalence. Important sources of error are the selection and attendance of patients, screening methods and diagnostic criteria. If routine examination does not include fundus photography and/or perimetry, the prevalence of NTG will be underestimated.
  •  
14.
  •  
15.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Intracranial and Intraocular Pressure at the Lamina Cribrosa : Gradient Effects
  • 2018
  • Ingår i: Current Neurology and Neuroscience Reports. - : Springer. - 1528-4042 .- 1534-6293. ; 18:5
  • Forskningsöversikt (refereegranskat)abstract
    • Purpose of Review: A pressure difference between the intraocular and intracranial compartments at the site of the lamina cribrosa has been hypothesized to have a pathophysiological role in several optic nerve head diseases. This paper reviews the current literature on the translamina cribrosa pressure difference (TLCPD), the associated pressure gradient, and its potential pathophysiological role, as well as the methodology to assess TLCPD.Recent Findings: For normal-tension glaucoma (NTG), initial studies indicated low intracranial pressure (ICP) while recent findings indicate that a reduced ICP is not mandatory.Summary: Data from studies on the elevated TLCPD as a pathophysiological factor of NTG are equivocal. From the identification of potential postural effects on the cerebrospinal fluid (CSF) communication between the intracranial and retrolaminar space, we hypothesize that the missing link could be a dysfunction of an occlusion mechanism of the optic nerve sheath around the optic nerve. In upright posture, this could cause an elevated TLCPD even with normal ICP and we suggest that this should be investigated as a pathophysiological component in NTG patients.
  •  
16.
  • Jóhannesson, Gauti, 1979- (författare)
  • Intraocular pressure : clinical aspects and new measurement methods
  • 2011
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Intraocular pressure (IOP) measurement is a routine procedure and a fundament in glaucoma care. Elevated IOP is the main risk factor for glaucoma, and to date, reduction of IOP is the only possible treatment. In a retrospective clinical material, the prevalence of open angle glaucoma was estimated on the west coast of Iceland. IOP measurement and optic nerve head examination were used to capture glaucoma suspects, within the compulsory ophthalmological examination for the prescription of eye glasses. The results were mainly in agreement with a recent prospective study in the same region. This indicated that retrospective data, under certain conditions, may contribute with useful information on the prevalence of glaucoma. However, normal tension glaucoma is underestimated if perimetry and/or fundus photography are not included in the examination. Three studies focused on the measurement of IOP. Goldmann applanation tonometry (GAT) is the standard method. GAT is affected by corneal properties, e.g. central corneal thickness (CCT) and corneal curvature (CC). Refractive surgery changes these properties. This has put focus on how corneal biomechanics translate into tonometric errors and stimulated the development of new methods. As a result, Pascal ® Dynamic Contour Tonometry (PDCT) and Icare® rebound tonometry have been introduced. A method under development by our research group is Applanation Resonance Tonometry (ART). It is based on resonance technology and estimates IOP from continuous measurement of force and contact area. Comparison of PDCT, Icare and GAT in a prospective study showed that the concordance to GAT was close to the limits set by the International Standard Organization (ISO) for PDCT, while Icare was outside the limits. To investigate if laser-assisted subepithelial keratectomy (LASEK) affects tonometry, a study was performed where measurements with GAT, PDCT and ART were obtained before, three and six months after LASEK. The hypothesis was that PDCT and ART would be less affected by LASEK than GAT. The results showed a statistically significant reduction of measured IOP three and six months after LASEK for all tonometry methods. Change in visual acuity and IOP between three and six months suggested a prolonged postoperative process. A servo-controlled prototype (ART servo) was developed. A study was undertaken to assess the agreement of ARTservo and a further developed v manual prototype (ART manual) with GAT. The study design was in accordance with the requirements of the ISO standard for tonometers. ARTmanual fulfilled the precision requirements of the ISO standard. ARTservo did not meet all the requirements of the standard at the highest pressure levels. Four tonometry methods, GAT, PDCT, Icare and ART, were investigated. None of them was independent of both CCT and CC. The inconsistencies in the results emphasize the importance of study design. A meta-analysis comprising healthy eyes (IOP ≤ 21 mmHg) in the three papers, revealed age as an important confounder. In summary, glaucoma prevalence in Iceland was investigated and the results indicated that a retrospective approach can contribute with meaningful information. ART and PDCT had a similar agreement to GAT. ART manual fulfilled the precision requirements set by the ISO-standard, ARTservo and PDCT were close, while Icare was distinctly outside the limits. All tonometry methods were affected by LASEK and no method was completely independent of corneal properties.
  •  
17.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Intraocular Pressure Decrease Does Not Affect Blood Flow Rate of Ophthalmic Artery in Ocular Hypertension
  • 2020
  • Ingår i: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology. - 0146-0404 .- 1552-5783. ; 61:12
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: To investigate if decrease of IOP affects the volumetric blood flow rate in the ophthalmic artery (OA) in patients with previously untreated ocular hypertension.METHODS: Subjects with untreated ocular hypertension (n = 30; mean age 67 +/- 8 years; 14 females) underwent ophthalmologic examination and a 3-Tesla magnetic resonance imaging investigation. The magnetic resonance imaging included three-dimensional high-resolution phase-contrast magnetic resonance imaging to measure the OA blood flow rate. The subjects received latanoprost once daily in the eye with higher pressure, the untreated eye served as control. The same measurements were repeated approximately 1 week later.RESULTS: The mean OA blood flow rate before and after treatment was 12.4 +/- 4.4 and 12.4 +/- 4.6 mL/min in the treated eye (mean +/- SD; P = 0.92) and 13.5 +/- 5.2 and 13.4 +/- 4.1 mL/min in the control eye (P = 0.92). There was no significant difference between the treated and control eye regarding blood flow rate before (P = 0.13) or after treatment (P = 0.18), or change in blood flow rate after treatment (0.1 +/- 3.1 vs.-0.1 +/- 4.0 mL/min, P = 0.84). Latanoprost decreased the IOP by 7.2 +/- 3.1 mm Hg in the treated eye (P < 0.01).CONCLUSIONS: The results indicate that a significant lowering of IOP does not affect the blood flow rate of the OA in ocular hypertension subjects. The ability to maintain blood supply to the eye independent of the IOP could be a protective mechanism in preserving vision in subjects with ocular hypertension.
  •  
18.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Introduction and clinical evaluation of servo-controlled applanation resonance tonometry
  • 2012
  • Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420 .- 1755-375X. ; 90:7, s. 677-682
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose:  In recent years, Applanation Resonance Tonometry (ART) has been suggested for intraocular pressure (IOP) measurements. The manual version of ART (ARTmanual) has been further developed, and to improve usability, an automatic servo-controlled prototype (ARTservo) has been proposed. The aim of this study was to assess the limits of agreement (LoA) of ARTmanual and ARTservo as compared with the reference method, Goldmann Applanation Tonometry (GAT).Methods:  This was a prospective single-centre study on 152 eyes from 77 subjects. It was designed according to International Standard Organization’s (ISO) requirements for tonometers (ISO 2001). Intraocular pressure was measured six times/method in a standardized order. The ART technique has two available analysis procedures: a dynamic one that measures IOP during the indentation phase and a static one that causes a Goldmann-like measurement during two seconds of full applanation. The 95% LoA was defined as ±1.96 × standard deviation of difference against GAT.Results:  Mean IOP for GAT was 19.1 mmHg (range: 10–37 mmHg). The 95% LoA of ARTmanual was ±4.5 mmHg for both dynamic and static analyses. The 95% LoA of ARTservo was ±5.7 mmHg for dynamic and ±4.9 mmHg for static analyses.Conclusions:  This study confirms that the ART methodology is feasible. The further developed ARTmanual fulfilled the ISO standard with both the dynamic and the static analysis techniques. ARTservo with static analysis was close to fulfilling the standard but failed to do so in the highest IOP range. ARTservo has the potential to greatly improve usability if further development is completed.
  •  
19.
  • Jóhannesson, Gauti, 1979-, et al. (författare)
  • Pascal, ICare and Goldmann applanation tonometry : a comparative study
  • 2008
  • Ingår i: Acta ophthalmologica. - : Wiley. - 1755-3768 .- 1755-375X. ; 86:6, s. 614-621
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: To compare intraocular pressure (IOP) measurements by Pascal, ICare and Goldmann applanation tonometry (GAT), to evaluate the effects of central corneal thickness (CCT) and curvature on IOP measurement and to estimate the intra-observer variability.METHODS: A prospective, single-centre study of 150 eyes with a wide range of pressures. Six masked IOP measurements/method; corneal thickness and curvature were studied for each eye. GAT was the reference.RESULTS: IOPPascal and IOPICare correlated with IOPGAT (r = 0.91, 0.89). Mean ICare measurement exceeded GAT by 2 mmHg. Pascal measured higher than GAT at low IOPs and lower at high IOPs. For every 10 mmHg increase in IOP above 31 mmHg, Pascal measured 2 mmHg lower than GAT and vice versa. CCT was correlated significantly with IOPGAT (r = 0.23) and IOPICare (r = 0.43) but not with IOPPascal (P = 0.12). CCT was correlated with age. In a subgroup (>50 years), ICare and the difference between IOPGAT and IOPPascal were affected significantly by the CCT, whereas IOPGAT and IOPPascal were not. Corneal curvature was correlated significantly with IOPGAT (r = -0.27) and IOPPascal (r = -0.26) but not with IOPICare (P = 0.60). Intra-observer variability within each set of six measurements was approximately 2 mmHg, irrespective of method.CONCLUSION: This study showed a reasonable overall correlation and concordance between the IOP obtained with the three instruments. None of the methods were completely independent of the biomechanical properties of the cornea. ICare showed a significant dependency upon CCT, whereas GAT and Pascal showed a significant dependency on corneal curvature. All methods showed intra-observer variability, which leaves room for further improvement of methods.
  •  
20.
  •  
21.
  • Kristiansen, Martin, et al. (författare)
  • Blood flow rate of ophthalmic artery in patients with normal tension glaucoma and healthy controls
  • 2018
  • Ingår i: Investigative Ophthalmology and Visual Science. - : The Association for Research in Vision and Ophthalmology. - 0146-0404 .- 1552-5783. ; 59:9
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Purpose: To determine the blood flow rate of the ophthalmic artery (OA) in patients with Normal Tension Glaucoma (NTG) compared to age-matched healthy controls using phase-contrast magnetic resonance imaging (PCMRI).Methods: Seventeen patients with treated NTG (11 female; mean age: 70±9 years) and 16 age-matched healthy controls (10 female; mean age: 71±9 years) underwent PCMRI using a 3-Tesla scanner as well as ophthalmological examinations including visual acuity, Goldmann Applanation Tonometry, Humphrey perimetry and fundoscopy. Ophthalmic blood flow was acquired using a 2D PCMRI sequence set to a spatial resolution of 0.35mm/pixel. Mean flow rate and cross-sectional area was calculated using Segment Software. The eye with the most severe glaucomatous damage classified by visual field index (VFI) was chosen for comparison. The primary outcome was blood flow rate of OA.Results: The mean VFI was 41% ± 26 (mean±SD) for the worse NTG eyes. The intraocular pressure was 13.6±2.6 mmHg for NTG eyes and 13.8±2.1 mmHg for control eyes. The blood flow rate in the NTG group was 9.6±3.7 ml/min compared to 11.8±5.5 ml/min in the control group. The area was 1.7±0.3 mm2 and 2.0±0.6 mm2 respectively. No statistical significance was found between NTG and the control group regarding blood flow rate (p=0.07) or OA area (p=0.12).Conclusions: Despite OA being an anastomosis between the intracranial and extracranial circulation, possibly generating an eye unrelated variability in blood flow, we found a trend level reduction of approximately 2 ml/min in NTG. The finding warrants blood flow rate analysis of smaller arteries specifically supplying the eye, e.g. the central retinal artery.
  •  
22.
  • Kristiansen, Martin, et al. (författare)
  • Feasibility of MRI to assess differences in ophthalmic artery blood flow rate in normal tension glaucoma and healthy controls
  • 2021
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 99:5, s. e679-e685
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To examine feasibility of phase-contrast magnetic resonance imaging (PCMRI) and to assess blood flow rate in the ophthalmic artery (OA) in patients with normal tension glaucoma (NTG) compared with healthy controls.Methods: Sixteen patients with treated NTG and 16 age- and sex-matched healthy controls underwent PCMRI using a 3-Tesla scanner and ophthalmological examinations. OA blood flow rate was measured using a 2D PCMRI sequence with a spatial resolution of 0.35 mm(2).Results: The blood flow rate in the NTG group was 9.6 +/- 3.9 ml/min [mean +/- SD] compared with 11.9 +/- 4.8 ml/min in the control group. Resistance Index (RI) and Pulsatility Index (PI) were 0.73 +/- 0.08 and 1.36 +/- 0.29, respectively, in the NTG group and 0.68 +/- 0.13 and 1.22 +/- 0.40, respectively, in the healthy group. The mean visual field index (VFI) was 46% +/- 25 for the worse NTG eyes. The measured differences observed between the NTG group and the control group in blood flow rate (p = 0.12), RI (p = 0.18) and PI (p = 0.27) were non-significant.Conclusions: This case-control study, using PCMRI, showed a slight, but non-significant, reduction in OA blood flow rate in the NTG patients compared with the healthy controls. These results indicate that blood flow may be of importance in the pathogenesis of NTG. Considering that only a limited portion of the total OA blood flow supplies the ocular system and the large inter-individual differences, a larger study or more advanced PCMRI technique might give the answer.
  •  
23.
  • Kristiansen, Martin, et al. (författare)
  • Optic nerve subarachnoid space posture dependency : an MRI study in subjects with normal tension glaucoma and healthy controls
  • 2023
  • Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 64:15
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: The purpose of this study was to examine the differences of optic nerve subarachnoid space (ONSAS) volume in patients with normal tension glaucoma (NTG) and healthy controls in different body positions.Methods: Eight patients with NTG and seven healthy controls underwent magnetic resonance imaging (MRI) examinations in head up tilt (HUT) +11 degrees and head down tilt (HDT) -5 degrees positions according to a randomized protocol determining the starting position. The ONSAS volume in both body positions was measured and compared between the two groups. The results were analyzed using a generalized linear model.Results: Between HDT and HUT, the postural ONSAS volume change was dependent on starting position (P < 0.001) and group (P = 0.003, NTG versus healthy). A subgroup analysis of those that were randomized to HUT examination first, coming directly from an upright position, showed that the patients with NTG had significantly larger positional ONSAS volume changes compared to the healthy controls; 121 ± 22 µL vs. 65 ± 37 µL (P = 0.049). Analysis of the ONSAS volume distribution showed different profiles for patients with NTG and healthy controls.Conclusions: There was a significant difference in ONSAS volume change between patients with NTG and healthy subjects when subjected to posture changes, specifically when going from upright to head-down posture. This indicates that patients with NTG had been exposed to a lower ONSAS pressure when they came from the upright posture, which suggests an increased translaminar pressure difference in upright position. This may support the theory that NTG has a dysfunction in an occlusion mechanism of the optic nerve sheath that could cause abnormally negative ONSAS pressures in upright posture.
  •  
24.
  • Linden, Christina, et al. (författare)
  • Initial intraocular pressure reduction by mono‐ versus multi‐therapy in patients with open‐angle glaucoma : results from the Glaucoma Intensive Treatment Study
  • 2018
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 96:6, s. 567-572
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To study newly diagnosed glaucoma patients given mono‐ or multi‐therapy regarding differences in initial intraocular pressure (IOP) reduction, target IOP levels reached and influence of untreated baseline IOP on IOP reduction.Methods: Patients newly diagnosed with manifest primary open‐angle glaucoma and included in the Glaucoma Intensive Treatment Study (GITS) were randomized to immediate intensive treatment with any of three different IOP‐lowering substances supplied in two bottles plus 360° laser trabeculoplasty or to conventional stepwise treatment starting with a single‐drug. Intraocular pressure reduction was analysed 1 month after initiation of treatment.Results: One hundred eighteen patients (143 eyes) received mono‐therapy and 122 patients (152 eyes) multi‐therapy. Median baseline IOP was 24.0 (min: 9.7, max: 56.0) mmHg in mono‐therapy eyes and 24.0 (min: 12.3, max: 48.5) mmHg in multi‐therapy eyes (p = 0.56). After 1 month in the two groups, respectively, values for median IOP reduction were 6.3 (range: −5.3–31.0) and 11.0 (range: 0.7–34.5) mmHg, and for mean relative decline 26.8 (range: −32.0–55.4) and 46.0 (range: 4.6–81.6) % (p = 0.000). A larger proportion of the multi‐therapy patients reached each target IOP level (p = 0.000). The higher the baseline IOP, the larger the observed pressure reduction, considering both absolute and relative figures. The effect was more pronounced in eyes with multi‐therapy than in those with mono‐therapy (p = 0.000). For every mmHg higher IOP at baseline, the IOP was reduced by an additional 0.56 (mono‐therapy) or 0.84 (multi‐therapy) mmHg.Conclusion: Intensive treatment led to considerably greater IOP reduction than mono‐therapy. Among patients with IOP ≥30 mmHg at diagnosis an IOP of <16 was reached in 2/3 of those with multi‐therapy but in none with mono‐therapy. The IOP reduction was highly dependent on the untreated IOP level.
  •  
25.
  •  
26.
  •  
27.
  • Lindén, Christina, et al. (författare)
  • Ögat
  • 2021. - 4
  • Ingår i: Kliniska färdigheter. - Lund : Studentlitteratur AB. - 9789144135885 ; , s. 275-292
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)
  •  
28.
  • Otmani, Amin, et al. (författare)
  • Prophylactic nicotinamide treatment protects from rotenone-induced neurodegeneration by increasing mitochondrial content and volume
  • 2024
  • Ingår i: Acta neuropathologica communications. - : BioMed Central (BMC). - 2051-5960. ; 12:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Leber’s hereditary optic neuropathy (LHON) is driven by mtDNA mutations affecting Complex I presenting as progressive retinal ganglion cell dysfunction usually in the absence of extra-ophthalmic symptoms. There are no long-term neuroprotective agents for LHON. Oral nicotinamide provides a robust neuroprotective effect against mitochondrial and metabolic dysfunction in other retinal injuries. We explored the potential for nicotinamide to protect mitochondria in LHON by modelling the disease in mice through intravitreal injection of the Complex I inhibitor rotenone. Using MitoV mice expressing a mitochondrial-tagged YFP in retinal ganglion cells we assessed mitochondrial morphology through super-resolution imaging and digital reconstruction. Rotenone induced Complex I inhibition resulted in retinal ganglion cell wide mitochondrial loss and fragmentation. This was prevented by oral nicotinamide treatment. Mitochondrial ultrastructure was quantified by transition electron microscopy, demonstrating a loss of cristae density following rotenone injection, which was also prevented by nicotinamide treatment. These results demonstrate that nicotinamide protects mitochondria during Complex I dysfunction. Nicotinamide has the potential to be a useful treatment strategy for LHON to limit retinal ganglion cell degeneration.
  •  
29.
  • Peters, Dorothea, et al. (författare)
  • Threat to fixation and vision-related quality of life in early open-angle glaucoma : results from the Glaucoma Intensive Treatment Study
  • 2023
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 101:1, s. 74-80
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To determine the effect of glaucomatous visual field (VF) damage close to the point of fixation, called threat-to-fixation (TTF), on vision-related quality of life (VRQoL) in open-angle glaucoma.Methods: A total of 239 patients from the Glaucoma Intensive Treatment Study (GITS) were included in this analysis. The second VF of patients with newly diagnosed primarily early glaucoma was evaluated for the presence or absence of TTF. TTF was defined as VF loss including one or more of the four innermost test points depressed at p < 1% in the total deviation probability map of Humphrey 24–2 SITA Standard visual fields. VRQoL was evaluated using Rasch-analysed National Eye Institute Visual Function Questionnaire 25 (NEI VFQ-25) scores. The correlation between VRQoL and TTF was evaluated using uni- and multivariable regression analyses.Results: TTF was present in at least one eye in 115 patients (48%); located in the superior hemifield alone in 47% (54 of 115), in the inferior hemifield alone in 23% (27 of 115), and in 30% (34 of 115) in both hemifields. The median Rasch-calibrated NEI VFQ-25 scores were identical when comparing patients with TTF (VRQoL score 66, 95% CI: 23–100) and those with no-TTF (VRQoL score 66, 95% CI: 21–100) (p = 0.925). Neither the presence of TTF (R2 = −0.004, p = 0.968) nor the location of TTF (R2 = 0.023, p = 0.103) was significantly correlated to Rasch-calibrated NEI VFQ-25 scores.Conclusion: The presence of TTF did not influence VRQoL, as measured by the NEI-VFQ-25, in this relatively large group of patients with mainly early glaucoma.
  •  
30.
  • Rasmuson, Erika, et al. (författare)
  • Changes in intraocular pressure during the first 24 h after transscleral cyclophotocoagulation
  • 2024
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768.
  • Tidskriftsartikel (refereegranskat)abstract
    • Aims: To estimate the changes in intraocular pressure (IOP) during the first 24 h after transscleral cyclophotocoagulation (TCP).Methods: A prospective single-centre study, where patients with glaucoma destined for treatment with TCP were asked for participation. The IOP was measured prior to TCP and at 1, 2, 4, 6 and 24 h post-TCP. An IOP spike was defined as an elevation of IOP of ≥5 mmHg compared with baseline. The visual acuity (VA) was examined at baseline and after 24 h.Results: The mean IOP prior to TCP in 58 eyes of 58 patients was 26.2 (±8.9 SD) mmHg. Twenty-three eyes (40%) experienced an IOP spike at some examination timepoint during the first 24 h. The mean value of the IOP spike was 12.1 (±6.9) mmHg. Fifty-six per cent of the eyes with pseudoexfoliation glaucoma (PEXG) experienced an IOP spike, and 16% had an IOP spike ≥20 mmHg. The IOP was significantly reduced at the 24 h examination by 8.1 (±7.8) mmHg (n = 58). The VA 24 h after TCP was unchanged compared with baseline.Conclusion: Clinically significant IOP spikes were common in the first 24 h post-TCP. Almost one in five eyes had an increase of 10 mmHg and in almost one in 10 eyes, the IOP increase was 20 mmHg or higher. Eyes with PEXG had a higher occurrence of IOP spikes and displayed a greater magnitude of IOP elevation. Prophylactic post-operative IOP-lowering medication should be considered to prevent further glaucoma damage.
  •  
31.
  •  
32.
  • Rasmuson, Erika, et al. (författare)
  • Efficacy and safety of transscleral cyclophotocoagulation in Swedish glaucoma patients
  • 2019
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 97:8, s. 764-770
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To retrospectively evaluate the efficacy and safety of all transscleral cyclophotocoagulation (TCP) treatments performed during a 5-year period.Methods: Medical records of all patients, who had undergone TCP treatment between 2010 and 2014 at Umea University Hospital, Sweden, were evaluated. Clinical data including intraocular pressure (IOP), visual acuity (VA), number of topical glaucoma medications, use of oral acetazolamide, retreatments and complications during a 2-year follow-up were registered. Global success was defined as IOP 6-18 mmHg with or without glaucoma medication. Results: Three hundred patients underwent TCP during the time period. Mean IOP at baseline was 29.3 11.0 (mean +/- standard deviation) mmHg (n = 297) with a mean reduction of 11.5 (+/- 12.0) mmHg at 1 year (n = 258; p < 0.001) and 12.6 (12.0) mmHg at 2-year follow-up (n = 245; p < 0.001). Global success at 2 years was 64%, achieved by a mean of 1.2 treatments (n = 257). The number of topical glaucoma medications at baseline was 3.1 (1.0; n = 296) and was reduced by 0.9 (+/- 1.0) medications at 2 years (n = 244; p < 0.001). Use of oral acetazolamide decreased from 30% (n = 90) at baseline to 5.3% (n = 13) at 2 years. In eyes with Snellen VA 0.1, the mean VA at baseline was 0.55 (+/- 0.3) logarithm of the minimum angle of resolution (logMAR; n = 132) and 1.1 (+/- 0.9) logMAR (n = 76) at 2 years (p < 0.001). No cases of phthisis bulbi were found.Conclusion: This study displays a substantial and long-term reduction of IOP following TCP with a decrease in topical and oral glaucoma medications. The treatment appears to be safe but the decrease in VA during follow-up is a concern that needs further evaluation.
  •  
33.
  • Rasmuson, Erika, et al. (författare)
  • Laser trabeculoplasty in newly diagnosed multi-treated glaucoma patients
  • 2021
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 99:3, s. 269-274
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To evaluate the intraocular pressure (IOP)‐lowering effect of laser trabeculoplasty (LTP) in eyes which IOP had been substantially reduced by intensive topical treatment for one week.Methods: Patients with newly diagnosed open‐angle glaucoma were randomized to treatment with three IOP‐lowering substances. One week later, 360° argon or selective LTP was performed. IOP was measured before LTP and at one‐, three‐, six‐ and 12‐month post‐LTP. The patients were part of the Glaucoma Intensive Treatment Study (GITS).Results: Mean IOP (± SD) in 152 eyes of 122 patients was 14.0 (± 3.5) mmHg just before LTP. For every mmHg higher IOP prior to LTP, the IOP was reduced by an additional 0.6 mmHg at 12 months. The IOP was significantly reduced at all follow‐up visits from −2.6 (± 3.1) mmHg at one month to −2.1 (± 3.8) mmHg at 12 months in eyes with pre‐LTP IOP ≥ 15 mmHg, while no significant IOP reduction was seen in eyes with pre‐LTP IOP < 15 mmHg. Older age, argon LTP and male sex were associated with larger IOP reduction after 12 months, whereas presence of exfoliation syndrome was associated with a smaller IOP reduction. No severe complications were reported.Conclusion: Success of LTP was highly dependent on the IOP level prior to LTP treatment. A sustained significant IOP reduction was seen in eyes with pre‐LTP IOP ≥ 15 mmHg whereas no such effect was seen in eyes with pre‐LTP IOP < 15 mmHg. Thus, LTP can be considered in eyes with multi‐treatment when target pressure of < 15 mmHg is not achieved.
  •  
34.
  • Rasmuson, Erika, 1981- (författare)
  • Laser treatment in glaucoma : efficacy and safety
  • 2023
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Glaucoma is a progressive optic neuropathy and the major cause of irreversible blindness worldwide. Although the pathogenesis of glaucoma is not completely understood, the most important risk factor for development and progression of the disease is an elevated intraocular pressure (IOP). Current glaucoma treatment aims to reduce the IOP in the affected eye. This can be achieved by topical drops, laser therapy or surgery. Laser treatment is used at different stages of the glaucoma disease. Some types of laser procedures are used as first-line treatments or as complement to topical medications or surgery, while other types are used in advanced glaucoma as a last option when other therapies have failed. Although laser therapy has long been used to reduce the IOP in glaucoma, knowledge gaps remain. The aim of this thesis was to evaluate the efficacy and safety, in both a short- and long-term perspective, of two of the most frequently used laser procedures in glaucoma: laser trabeculoplasty (LTP) and transscleral cyclophotocoagulation (TCP).In the first study, a retrospective analysis, the long-term efficacy and safety of TCP was evaluated in 300 eyes of 300 glaucoma patients in northern Sweden. We found an overall substantial IOP reduction of more than 10 mmHg that was maintained at least 2 years in various types of glaucoma. Following TCP, the patients could reduce their treatment with an average of one substance of topical glaucoma medication in the treated eye. No case of phthisis bulbi, the most feared complication of TCP, was reported. However, a general decline in visual acuity (VA) was noted during the two-year follow up period, and the cause of this finding was difficult to assess due to the retrospective nature of the study.The short-term effect of TCP on IOP was further investigated in a prospective study of 58 eyes of 58 glaucoma patients. IOP was measured at baseline before TCP and at five additional time-points up to 24 hours after the treatment. The VA was measured before TCP and at the 24 h examination. The results showed a transient IOP spike with a peak at six hours after TCP in approximately 40% of the eyes. Spikes were more common in eyes with pseudoexfoliation glaucoma.The last two studies of the thesis focused on the short- and long-term efficacy of LTP. One-hundred fifty-two eyes of 122 newly diagnosed glaucoma patients that had been randomized to the multi-treated arm in the Glaucoma Intensive Treatment Study (GITS) were included. All studied eyes were treated with three different IOP-lowering substances and after one week, LTP was performed. We demonstrated that there was an additional IOP-lowering effect of LTP but that this effect was strongly associated with the level of IOP before the laser, where a higher IOP pre-LTP yielded a greater IOP reduction. Eyes with pre-laser IOP ³15 mmHg showed a significant IOP reduction that was maintained during four years of follow-up. However, in eyes with pre-LTP IOP <15 mmHg, the effect of laser treatment was limited.In summary, this thesis investigated the efficacy and safety of TCP both retrospectively in a longer perspective and prospectively during the first 24 hours after treatment. An overall high efficacy without serious complications was shown, but a possible decline in VA must be considered in the long run. Furthermore, the risk of IOP spikes after TCP implies that additional IOP-lowering treatment should be considered during the first 24 hours, especially in eyes with pseudoexfoliation glaucoma or severe glaucoma damage. Finally, LTP may provide a valuable long-lasting IOP-lowering effect despite medical multi-treatment in eyes with a pre-LTP IOP ³15 mmHg.
  •  
35.
  • Rasmuson, Erika, et al. (författare)
  • Long-term follow-up of laser trabeculoplasty in multi-treated glaucoma patients
  • 2024
  • Ingår i: Acta Ophthalmologica. - : John Wiley & Sons. - 1755-375X .- 1755-3768. ; 102:2, s. 179-185
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To evaluate the long-term effect of laser trabeculoplasty (LTP) in patients randomized to multi-treatment in the Glaucoma Intensive Treatment Study (GITS).Methods: Patients with untreated newly diagnosed open-angle glaucoma were treated with three intraocular pressure (IOP)-lowering substances for 1 week and then 360 degrees argon or selective LTP was performed. IOP was measured just before LTP and repeatedly during the 60-month study period. Our previous report on 12 months follow-up data revealed no effect of LTP in eyes having an IOP <15 mmHg before the laser treatment.Results: Before LTP, the mean IOP +/- standard deviation in all 152 study-eyes of 122 multi-treated patients was 14.0 +/- 3.5 mmHg. Three eyes of three deceased patients were lost to follow-up during the 60 months. After exclusion of eyes that received increased therapy during follow-up, the IOP was significantly reduced at all visits up to 48 months in eyes with pre-LTP IOP >= 15 mmHg; 2.6 +/- 3.1 mmHg at 1 month and 1.7 +/- 2.8 mmHg at 48 months, n = 56 and 48, respectively. No significant IOP reduction was seen in eyes with pre-LTP IOP <15 mmHg. Seven eyes, i.e., <13%, with pre-LTP IOP >= 15 mmHg at baseline had required increased IOP-lowering therapy at 48 months.Conclusion: LTP performed in multi-treated patients may provide a useful IOP reduction that is maintained over several years. This was true on a group level when the initial IOP was >= 15 mmHg, but if the pre-laser IOP was lower than that, chances of LTP success were small.
  •  
36.
  • Rutigliani, Carola, et al. (författare)
  • Widespread retina and optic nerve neuroinflammation in enucleated eyes from glaucoma patients
  • 2022
  • Ingår i: Acta neuropathologica communications. - : BioMed Central. - 2051-5960. ; 10:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Neuroinflammation is recognized as a key component of neurodegenerative disease. In glaucoma, a common neurodegenerative disease and the leading cause of irreversible blindness, the evidence for neuroinflammation in patients is lacking. Animal models have demonstrated significant pro-inflammatory activation of resident glia in the retina, as well as influx of blood-derived monocytes and pro-inflammatory factors. Confirmation of this in human donor tissue has been challenging due to a lack of well-preserved and well-characterized post-mortem tissue. To address this we utilize archived, wax embedded eyes fixed immediately following enucleation from living glaucoma patients. We compared glaucoma to control eyes (enucleated for uveal melanoma where the tumor did not impact the central retina or optic nerve). We performed immunolabelling for neurodegenerative and glial markers (CD45, CD163, IBA1, GFAP, Vimentin) which were quantified by high-resolution light microscopy and image analysis in FIJI. Glaucoma eyes demonstrated significant neural loss consistent with advanced neurodegeneration. IBA1 and GFAP were significantly increased in the retina and optic nerve head of the glaucomatous eyes indicating that significant neuroinflammation had occurred which support findings in animal models. Inflammation is a treatable symptom of many diseases and as such, identification of earlier inflammatory processes in glaucoma could be important for potential future treatment options.
  •  
37.
  • Tribble, James R., et al. (författare)
  • Nicotinamide provides neuroprotection in glaucoma by protecting against mitochondrial and metabolic dysfunction
  • 2021
  • Ingår i: Redox Biology. - : Elsevier. - 2213-2317. ; 43
  • Tidskriftsartikel (refereegranskat)abstract
    • Nicotinamide adenine dinucleotide (NAD) is a REDOX cofactor and metabolite essential for neuronal survival. Glaucoma is a common neurodegenerative disease in which neuronal levels of NAD decline. We assess the effects of nicotinamide (a precursor to NAD) on retinal ganglion cells (the affected neuron in glaucoma) in normal physiological conditions and across a range of glaucoma relevant insults including mitochondrial stress and axon degenerative insults. We demonstrate retinal ganglion cell somal, axonal, and dendritic neuroprotection by nicotinamide in rodent models which represent isolated ocular hypertensive, axon degenerative, and mitochondrial degenerative insults. We performed metabolomics enriched for small molecular weight metabolites for the retina, optic nerve, and superior colliculus which demonstrates that ocular hypertension induces widespread metabolic disruption, including consistent changes to α-ketoglutaric acid, creatine/creatinine, homocysteine, and glycerophosphocholine. This metabolic disruption is prevented by nicotinamide. Nicotinamide provides further neuroprotective effects by increasing oxidative phosphorylation, buffering and preventing metabolic stress, and increasing mitochondrial size and motility whilst simultaneously dampening action potential firing frequency. These data support continued determination of the utility of long-term nicotinamide treatment as a neuroprotective therapy for human glaucoma.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-37 av 37
Typ av publikation
tidskriftsartikel (32)
doktorsavhandling (2)
annan publikation (1)
forskningsöversikt (1)
bokkapitel (1)
Typ av innehåll
refereegranskat (30)
övrigt vetenskapligt/konstnärligt (7)
Författare/redaktör
Jóhannesson, Gauti, ... (36)
Lindén, Christina (24)
Eklund, Anders, 1965 ... (10)
Bengtsson, Boel (7)
Heijl, Anders (7)
Aspberg, Johan (7)
visa fler...
Andersson-Geimer, Sa ... (6)
Hallberg, Per (5)
Wåhlin, Anders (4)
Kristiansen, Martin (4)
Lundberg, Björn (3)
Barkander, Anna (3)
Ambarki, Khalid (3)
Malm, Jan, Professor ... (3)
Qvarlander, Sara, Te ... (3)
Wiklund, Urban (2)
Eklund, Anders (2)
Economou, Mario A. (2)
Johansson, Elias (2)
Qvarlander, Sara (2)
Brautaset, Rune (2)
Bergström, Anders (1)
Nilsson, Mattias (1)
Malm, Jan (1)
Wahlin, Anders (1)
Eklund, Anders, Doce ... (1)
Andersson, Sabina (1)
Karlsson, Markus (1)
Azuara-Blanco, Augus ... (1)
McCorry, Noleen (1)
Tatham, Andrew J. (1)
Georgoulas, Stelios (1)
Founti, Panayiota (1)
Schweitzer, Cedric (1)
Meier-Gibbons, Franc ... (1)
Denis, Philippe (1)
Tuulonen, Anja (1)
De La Casa, José Mar ... (1)
Prokosch, Verena (1)
Giannoulis, Dimitrio ... (1)
Abegão Pinto, Luis (1)
Garway-Heath, David (1)
Topouzis, Fotis (1)
Nolan, Andrew S. (1)
Economou, M.A. (1)
Lindén, Christina, p ... (1)
Kalaboukhova, Lada, ... (1)
Lindqvist, Anna (1)
Kolko, Miriam (1)
Stefansson, Einar (1)
visa färre...
Lärosäte
Umeå universitet (37)
Lunds universitet (8)
Karolinska Institutet (6)
Göteborgs universitet (1)
Linköpings universitet (1)
Språk
Engelska (36)
Svenska (1)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (37)
Naturvetenskap (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy